I cannot comment on which tires will work on your Competition but I suspect that going with 700c wheels will open up more possibilities in tire width. My Competition GS came standard with 700c wheels and I am currently running 23's but could probably run 28's if I wanted. The Competition went through a few changes but also share similarities from the early to the late seventies . Mine is the first year of the Campy version , 1977 . I don't know if the original geometry changed , but lugs , drop outs , and chrome did , as well as components. What works on my Competition may not work on yours.